The present invention relates to a metal bellows core and to a method of fabricating a metal bellows core.
Metal bellows assemblies, typically consisting of a bellows core joined to end fittings or component mating parts, are useful in applications where media, extreme temperature, pressure or radiation problems preclude the use of traditional elastomeric devices. Applications for metal bellows assemblies include shaft seals, expansion joints, flexible vacuum connections, pneumatic controllers, sensors, actuators and switches. Conventional metal bellows cores are formed in one piece or are fabricated by welding together adjoining annular metal diaphragms. Typically, the bellows core is joined to end fittings or component mating parts by soldering, brazing or welding.
In fabricating a conventional metal bellows core by welding together a series of annular diaphragms or plates, numerous individualized joining steps are typically required. This inability to form all joints simultaneously increases costs and job lead-time. In addition, in a welded metal bellows, the thickness of weld-bead or "nugget" which is formed at the edge joints will exceed the combined thickness of the plates or surfaces being joined. Since the abutting of the weld-beads of adjacent joints will prevent full compression of the bellows core, complete "nesting" and broad-based support of the adjacent diaphragm members upon collapse of the bellows core will not be possible.